The disclosure relates generally to combustion systems, and more particularly, to a vaporization system for a combustion system of, for example, a gas turbine system.
Gas turbine systems generate power by burning a fuel in a combustion system and directing a flow of combusted fuel to drive a turbine to generate power. A combustion system of the gas turbine system may burn a variety of hydrocarbon fuels in a combustor thereof. For example, combustors commonly burn both liquid and gas fuels. Liquid fuels may include, for example, fuel injected oil, and gas fuels may include, for example, natural gas. Each fuel is typically conditioned by respective liquid or gas fuel conditioning and control systems upstream of the combustor. Conditioning and control systems may include control a variety of factors such as, for a liquid fuel: removal of unwanted liquids (e.g., water) or materials (e.g., sediment), performance fuel heating, splitting of fuel flow to different combustor elements, distribution of fuel to various combustors by controlling a number of valves, etc.
Gas fuels are delivered to a gas fuel conditioning and control system under pressure either directly or from a vaporization system that delivers or stores them as liquid and vaporizes them as needed. For conventional gas fuel, such as methane (CH4), the gas may be delivered, via a supply pipeline, to a gas fuel conditioning and control system.
Currently, other liquid hydrocarbons usable for a gas turbine combustion system are increasingly available. For example, ethane, propane, butane, iso-pentane, are more readily available. Use of these liquid hydrocarbons presents a challenge, however, because they transition from a liquid to a vapor quickly through pressure reduction that creates excessive adiabatic cooling. The adiabatic cooling is oftentimes sufficient to decrease local temperatures below material property limits (e.g., of a holding receptacle and/or related system's), potentially reducing material structural strength capabilities. Further, expansion from liquid to vapor occurs when filling a low pressure (e.g., ambient pressure) vessel with a liquid hydrocarbon, which impedes or delays formation of a measurable and controllable liquid level such that vaporization can be controlled in a conventional manner, e.g., via controlled heating of the liquid hydrocarbon with a stable controlled liquid level. One approach to addressing the challenge is to select holding receptacle material properties capable of withstanding the temperatures that occur during adiabatic cooling when filling the holding receptacle. However, such materials increase the cost of such holding receptacles. Another approach is to reduce the liquid hydrocarbon temperature to extremely low conditions (e.g., below dew point) resulting in the hydrocarbon remaining in liquid form during the high to low pressure transition. This approach however is impractical and excessively costly.